Tuesday, March 28, 2017

Carbon Culprit

Let’s face it, we are all power pigs.  We love our electric appliances and cars.  Who among us does not appreciate jetting to far-off lands?  Then of course, there is the comfort of air conditioners and furnaces that keep our homes and offices at the perfect temperature.  The problem is that all these seemingly indispensible conveniences have been produced with fossil fuels that are the sources of greenhouse culprits leading to global warming.

The amount of carbon dioxide produced when a fossil fuel is burned is a function of the carbon content of the fuel.  True enough, as shown in the table below, not all fuels are created equal.

Fuel Source
Pounds of Carbon
per Million Btu
Coal, anthracite
Coal, bituminous
Diesel fuel
Natural gas
Source:  U.S. Energy Information Administration

Of course, the table above shows only the carbon emissions from actually burning the fuel.  If the original production process is also taken into consideration, i.e. the lifecycle of the fuel source, then carbon emissions for every source would be higher.  It is also valuable to see the conventional fossil fuel sources alongside renewable energy sources, as shown in the table below.

Power Source
Gram Carbon Dioxide per Kilowatt Hour
Coal, all types
Natural gas
Biomass, dedicated
Solar, photovoltaic
Solar, concentrating
Source:  National Renewable Energy Laboratory, Intergovernmental Panel on Climate Change

The data in the second table makes it clear that shifting our power generation and transportation fuels to renewable sources reduces but does not eliminate carbon dioxide emissions.  True enough the conversion of electricity generation from a coal-fired power plant to hydropower, as an example, leads to a 97% reduction in greenhouse gas emissions.  That is a powerful change.   
There are some technologies and process tweaks that can deliver at least partial redemption for the fossil fuels.  For example, coupled with carbon capture and storage, the lifecycle greenhouse gas emissions from natural gas can be reduced to as low as 245 grams of carbon dioxide per kilowatt hour from 650.  That puts natural gas much closer to the emissions neighborhood where we find photovoltaic systems and well below biomass fuel sources for power generation. 
Additionally, there are some technologies under development that may be able to redeem coal.  One possibility is the use of pulverized or powdered coal blown into the firebox at coal-fire powered plants.  This would lead to far more efficient use of the furnace capacity and reduce the amount of coal that has to be burned for the same power generation.  Using pulverized coal could reduce greenhouse gas emissions to 250 grams per kilowatt hour.  However, integrating a high pressure gasifier into a coal-fired power plant could lead to even better results.  First the coal is converted to synthetic gas.  Impurities such as sulfur and mercury are removed and turned into commercially valuable by-products.  With sequestration of any remaining carbon dioxide such plants could have a lifecycle greenhouse gas emission level of 230 grams per kilowatt hour.
The next few posts will look at the companies developing technologies that could lead to environmental redemption for some of these carbon culprits.

Neither the author of the Small Cap Strategist web log, Crystal Equity Research nor its affiliates have a beneficial interest in the companies mentioned herein.

No comments: